Change Of Mitochondrial Transmembrane Potential During The Different Preconditioning Phase Of Noradrenaline's Treatment

Part 1 Change of transmembrane potential during the early preconditioning phase of Noradrenaline's treatmentObjective To investigate the change of transmembrane potential during Noradrenaline's early preconditioning phase and probe the mechanism of action.Methods Primary culture myocardial cell of neonate rat were divided into three groups at random. GroupⅠis control group, GroupⅡis treatment group by hypoxia, Group III is treatment group by NA. GroupⅠdidn't give any drug to culture for 40minutes; GroupⅡtreated for 40minutes by hypoxia, Group III exposed to Noradrenaline (0. 2μg/ ml) for 10 minutes then treated with hypoxia for 40 minutes. The fluorescence intensity of rhodamine-123 marked mitochondria were detected by flow cytometry.Results The fluorescence intensity of three Group were test by analysis of variance (F=461.3, p<0.05) The fluorescence intensity of Group HP and Group NAPC is lower than Group CON (6.24±0.13%, 6.55±0.17% vs. 8.32±0.19%, p<0.05). The transmembrane potential of Group HP and Group NAPC is lower than Group CON which indicated the energy synthesis is not enough. The fluorescence intensity of Group NAPC is higher than Group HP. The transmembrane potential of Group NAPC is higher than Group HP which indicated the energy synthesis of Group HP is not enough.Conclusion The fluorescence intensity of Group NAPC is higher than Group HP which indicate the transmembrane potential of Group NAPC is higher during the early preconditioning of NA. NA can strengthen tolerance of myocardial cell. Part 2 Change of transmembrane potential during the delayed preconditioning phase of Noradrenaline's treatmentObjective To investigate the change of transmembrane potential during Noradrenaline's delayed preconditioning phase and probe the mechanism of action.Methods Primary culture myocardial cell of neonate rat were divided into three groups at random. GroupⅠis control group, GroupⅡis treatment group by hypoxia, Group III is treatment group by NA. GroupⅠdidn't give any drug to culture for 24 hours; GroupⅡcultured for 24 hours without any drugs, then treated for 40minutes by hypoxia, Group III exposed to Noradrenaline (0. 2μg/ ml) for 10 minutes, then treated with hypoxia for 40 minutes after cultured 24 hours. The fluorescence intensity of rhodamine-123 marked mitochondria was detected by flow cytometry.Results The fluorescence intensity of three Group were test by analysis of variance (F=355.5, p<0.05) The fluorescence intensity of Group HP and Group NAPC is lower than Group CON (6.24±0.13%, 6.68±0.22% vs. 8.32±0.19%, p<0.05). The transmembrane potential of Group HP and Group NAPC is lower than Group CON which indicated the energy synthesis is not enough. The fluorescence intensity of Group NAPC is higher than Group HP. The transmembrane potential of Group NAPC is higher than Group HP which indicated the energy synthesis of Group HP is not enough.Conclusion The fluorescence intensity of Group NAPC is higher than Group HP which indicates the transmembrane potential of Group NAPC is higher during the delayed preconditioning of NA. NA can strengthen tolerance of myocardial cell.